Background: Food insecurity increases one's risk for obesity, diabetes, hypertension, and cancer (via its links to poor diet and nutrition), conditions highly prevalent among Native Americans in Oklahoma (obesity 42%, diabetes 15%, and hypertension 38%).1 Our pilot study shows that 3 times as many Natives in Oklahoma are food insecure as Whites (21.3% vs. 7.3% respectively).2 Yet few or no studies have assessed individual- and environmental-level correlates of food insecurity among Natives and none have developed interventions or broad-based educational materials within Oklahoma tribal nations.3,4 Aims and Methods: This study, led by a Native American Choctaw Investigator will, Aim #1: Assess correlates (sociodemographics, health behaviors, perceived food environment) and outcomes (dietary intake including vegetables and fruits, BMI, diabetes, and hypertension) of food insecurity in the Chickasaw and Choctaw nations in Oklahoma. A telephone survey will be administered to 500 Native American adults (18+) randomly sampled from tribal registries. Clinical measures will be validated for 200 of those surveyed using tribal clinic electronic health records. Perceptions of food environments will be compared to objective store measures using GIS data. Aim #2: Design, implement, and evaluate a convenience store intervention to increase the availability and intake of vegetables and fruits among tribal members. Using a cluster-randomized design with 20 matched tribally owned convenience stores (5 cases and 5 controls in each tribe), we will implement evidence-based strategies (increased availability and variety, point of purchase information, reduced prices/coupons) to increase the sales and intake of vegetables and fruits among tribal members. Store-level changes will be measured by pre/post sales records and the Nutrition Environment Measures Survey; individual-level changes by two cross-sectional surveys, administered to 300 convenience store shoppers before and 300 shoppers after the intervention. Tribal members will use video voice,3 an action-oriented participatory media research method to collect qualitative and environmental data (e.g. types of foods/beverages sold and promoted in the convenience stores) to facilitate community planning and channel recommendations to policy makers. Aim #3: Create a multimedia manual, co-developed with tribal members, guiding tribes in food environment changes, and disseminated over a free and open source Website allowing for tribal user- created content. Innovation: Each of the 3 aims builds on our preliminary data and/or best practices, and leverages tribal resources and partnerships to enhance survey participation rates and convenience store healthy makeovers. Significance and Impact: The knowledge from surveys on food insecurity correlates and health outcomes will inform the design of the convenience store intervention to increase availability of vegetables and fruits. The resulting multimedia manual will guide food environment changes among tribes nationally to address the critically high rates of obesity, diabetes, and hypertension within this population.